1 / 9

SO 2

SO 2. Reading: Chap 15. Strategies for SO 2 removal Formation Prevention Low sulfur fuel, Fuel desulfurization, Flue Gas Treatment Wet scrubbing, Dry scrubbing, Spray drying, Dual Alkali, Wellman-Lord Process. Strategies for SO 2 Removal. Fuel Desulfurization. Oil & natural gas. Coal.

jana
Télécharger la présentation

SO 2

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. SO2 Reading: Chap 15 • Strategies for SO2 removal • Formation Prevention • Low sulfur fuel, Fuel desulfurization, • Flue Gas Treatment • Wet scrubbing, Dry scrubbing, Spray drying, Dual Alkali, Wellman-Lord Process Aerosol & Particulate Research Laboratory

  2. Strategies for SO2 Removal Aerosol & Particulate Research Lab

  3. Fuel Desulfurization Oil & natural gas Coal Mineral sulfate --> wash away Organic sulfur ??? --> SO2 removal IGCC – Integrated Gasification Combined Cycle Claus process (for sale; a commodity, not a pollutant) SO2 Removal High concentration (e.g. smelting) Absorbing SO2 to make H2SO4 Low concentration (< 2000 ppm) Flue gas desulfurization Aerosol & Particulate Research Lab

  4. Limestone (Wet) Scrubbing (packed tower) (effluent hold tank) Q: Advantages and disadvantages compared to water? Mass transfer in liquid film f: enhancement factor Overall mass transfer coefficient Q: Does mass transfer increase as f increases? Main reactions converting SO2 to bisulfite in the liquid film precipitate Aerosol & Particulate Research Lab

  5. Q: Is it better to have a high pH? Aerosol & Particulate Research Lab

  6. Lime (Wet) Scrubbing Q: How does it compare to limestone scrubbing? Dual Alkali (recycled) Q: Advantages and disadvantages? Aerosol & Particulate Research Lab

  7. CaO Ca2+ Ca2+ SO2 CaO CaSO4 CaSO4 Lime-Spray Drying Same as lime scrubbing except the water evaporates before the droplets reach the bottom of the tower Dry scrubbing Direct injection of pulverized lime or limestone, also trona (natural Na2CO3) or nahcolite (natural NaHCO3) Q: Advantage of dry methods over wet methods? Aerosol & Particulate Research Lab

  8. Wellman-Lord (W-L) process (1) Flue gas pretreatment: (venturi prescrubber) to remove particulates, SO3 and HCl (2) SO2 absorption by Na2SO3 solution No further SO2 absorption (3) Purge treatment: centrifuge the slurry to remove solids (4) Na2SO3 regeneration Claus process (concentrated, 85%) (make-up sodium) (averagely, 1 mole Na2SO3 for 42 moles of SO2) Westvaco process Aerosol & Particulate Research Lab

  9. Quick Reflection Aerosol & Particulate Research Lab

More Related